Identity function - the head

[timelets]

On seeing the state of his brother-in-law, the husband was also moved deeply and he decided to offer his own head too to the goddess and cut his own head with his scitmar.

Madanasundari, after a long wait came and saw both her brother and husband lying on the ground and then decided to take her own life but asked the goddesss to get the same brother and husband in the next life. The goddess was pleased and stopped her from dying and asked her to join their heads and bodies and then she granted them life. In a hurry, Madanasundari, confused the heads of her brother and husband and was perplexed.

Betaal stops and asks King Vikram this question: Who among the two is the husband of Madanasundari? Vikram replies with a lot of thought, "The body that carries her husband's head is is her husband. The head is the most important part of the human body, and the rest of the body is identified by the head."

f: A -> B  // removing the head;
g: B ->A // attaching the head;

gf = 1_A